AN EXPERIMENTAL STUDY OF REGENERATION IN THE FRONTAL SINUS AND THE RELATIONSHIP BETWEEN PNEUMATISATION OF THE SINUS AND DUCTUS OF THE FRONTAL SINUS DURING DEVELOPMENT

Author used 30 kids in an experimental study to observe the re-pneumatisation of the frontal sinus after the operation and to observe relation- ship between the sinus and the ductus nasofron- talis during development. The kid's frontal sinus was most suitable for the experimental study of regeneration, because each kid's frontal sinus had difference in its growth degree or pneumatisation. As the experimental method, author observed the difference of the re-pneumatisation phenome- non of the frontal sinus occurred in the degree of removal of .the facial wall and in the existence of clossure of the ductus nasofrontalis, and the relativity between the components of the sinus and its ductus nasofrontalis. The following results were obtained. 1) Between the differece of pneumatisation of the frontal sinus and ductus nasofrontalis, the relativity was that the ductus nasofrontalis, was small in bad pneumatisation cases and the ductus nasofrontal is was large in good pneumatisation cases of its frontal sinus. 2) Granulation-increase was stronger from the eary time in the wide removed group than in the preserved group of the facial wall. And the frontal sinus was obliterated comple- tely within 6 months in the fromer, on the other hand, in the latter the frontal sinus was not obli- terated, although the reduction of its sinus was noticed. In these cases, obliteration or reduction of the sinus was more speedy in the cases of bad pneumatisation of the frontal sinus befor operative procedure. 3) In the sides found of closurer of the duc- tus nasofrontalis, granulation-increase was stronger and obliteration or reduction of sinus was more speedy than the sides remaining the ductus fron- talis. 4) Re-pneumatisation began after 6 months in the wide removed group and after 5 months in the preserved group of the facial wall. In these cases, the time of re-pneumatisation of the sinus was earier in the good pneumatisation before the operation. 5) Re-pneumatisation of the sinus was seen in the side remaining the ductus nasofrontalis, on the other hand, in the side noticed of closure of the ductus re-pneumatisation was not found. 6) By keeping a condition of artificial control- led pneumatisations-suppression, the ductus naso- frontalis became large and in addition, the hyper- function of the mucous membrane of the ductus was showed microscopically, in agreement with definite days or months after the operation. This fact agreed with the theory in the deve- lopmental process between the ductus and sinus which were found in common pneumatic organ.